Find extension builders near me

An extension builder designs and constructs additional living space for your home.

If your family needs more room or you’re ready to improve how your home works day to day, finding the right builder matters.

This guide explains how to find experienced extension builders near you, what the job involves, and how to choose a team you can trust with such an important project.

How to find trusted local extension builders near you

Finding the right builder for your extension doesn’t need to feel overwhelming. A few simple steps can help you compare options and move forward with confidence.

1. Search your postcode

Browse checked and reviewed extension builders working in your area, whether you're in Brighton, Bath, Bognor or any other part of the UK.

2. Compare options

Browse company profiles, check verified reviews from past projects, and look for experience with similar extensions.

3. Request quotes

Use our request-a-quote tool to receive a selection of quotes to compare pricing, services offered and availability.

4. Use the Checkatrade app

Track messages, quotes, and project updates all in one place.

Find reputable extension builders in your area with Checkatrade

Only tradespeople who pass our checks and commit to the Checkatrade Standard appear in our listings.

That means you can compare options knowing they’ve met clear standards for quality and conduct.

To find experienced local extension builders, simply enter your postcode and start browsing.

"I thought renovations were supposed to be stressful? Not with Shaz and his team. From the start, the process was smooth, well-managed, and even enjoyable. We had a dedicated project manager, and Gagan, our on-site lead, kept everything on track and communicated clearly. The team was responsive, stuck to quoted prices and timelines, and guided us with honest, helpful advice. Our full house renovation included electrics, plumbing, and more — every vendor recommended was excellent. The result speaks for itself. We’d recommend them without hesitation."

Verified review, SM London Construction, (Location HA4)

Find extension builders who work in your local area

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Find related services you may need

• Architects near me

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Why hire an extension builder

Hiring a builder who specialises in extensions can make a real difference to how smoothly your project runs and how confident you feel throughout the process.

The benefits of choosing an extension specialist include:

• Experience managing complex building work from start to finish

• Understanding of structural changes and safe construction methods

• Ability to coordinate multiple trades and keep work on schedule

• Understanding of planning permission and permitted development rules, helping you avoid delays or unexpected issues

• Clear communication about timelines, progress and next steps

• Confidence that the finished space will be safe, durable and built to last

What does the role of an extension builder involve?

Building an extension is a structured process that involves planning, construction and finishing work. While every project is slightly different, most follow a similar sequence.

Step 1: Initial consultation and site assessment

First, your builder will discuss your ideas, assess the space and identify any practical considerations.

Step 2: Preparing the site

This may involve groundwork, foundations and preparing the structure for building work.

Step 3: Constructing the extension

The walls, roofing and structural elements are then built to create the new space.

Step 4: Installing services and finishing work

Finally, electrical, plumbing and internal finishes are completed before final checks and handover.

Kitchen extension by SM London Construction Ltd

What affects the outcome of an extension project?

Several practical factors can influence how smoothly an extension project runs and the quality of the finished result, including:

• Type and size of the extension

• Ground conditions and structural requirements

• Access to the property

• Weather conditions during construction

• Experience of the building team

These are the kinds of details an experienced extension builder will assess early on to avoid delays or unexpected costs.

Kitchen extension (before & after) by SM London Construction Ltd

How much does an extension cost?

Extension costs vary widely depending on the size, design and complexity of the project, but as a general guide, the cost of a house extension typically ranges from £1,800–£3,000 per m².

Factors such as materials, structural work and location can significantly affect the final price.

Average single-storey extension costs

• A standard small extension (20m²) might cost between £40,000–£56,000

• A mid-sized extension (30m²) might cost around £60,000–£84,000

• A large extension (50m²) extension could set you back between £100,000 – £140,000

Average double-storey extension costs

• A typical 60m² two-storey house extension tends to cost in the region of £108,000–£180,000

For a more detailed cost breakdown, see our extension cost guide.

What affects the cost of hiring an extension builder?

The total cost of your extension will depend on several key factors, including:

• The size of the extension

• Labour time

• Materials and finishes

• Structural work required

• Access to the property

• Your location

When choosing a contractor, compare itemised quotes from several local extension builders to understand what's included and ensure fair pricing.

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Common mistakes to avoid when hiring an extension builder

• Choosing based on price alone

• Not checking insurance or credentials

• Failing to confirm what the quote includes

• Not comparing itemised quotes

• Ignoring verified reviews

Taking time to review these details can help prevent delays, misunderstandings and unexpected costs.

We check the reviews on Checkatrade are from real people, and that trades meet our high standards.

Questions to ask before hiring an extension builder

• Do you have adequate and up to date insurance and can you provide evidence?

• What does your quote include?

• How long will the project take from start to finish?

• Will you coordinate other trades involved in the build?

• Do you offer any warranty or guarantee on the work?

On Checkatrade, you'll only find trades who meet our high standards and pass up to 12 checks.

"It’s been an absolute pleasure from start to finish. Steve is a brilliant builder and a genuinely great bloke too. His team are reliable, respectful, and incredibly hard-working, ensuring every detail of the job is completed to the highest standards. The work was done at a reasonable price, and they maintained a clean and tidy workspace throughout the entire project. Steve’s project management skills are exceptional — he kept everything on track and ensured the job ran smoothly and to the highest standards. We are absolutely thrilled with the outcome and would highly recommend Titan construction"

Verified review, Titan Construction, (Location BN15)

Why use Checkatrade to find trusted local extension builders?

• Checked - Every Checkatrade member must pass up to 12 checks and commit to upholding the Checkatrade Standard

• Reviewed - Over 6.2 million verified reviews from real jobs have been published on Checkatrade on everything from communication, tidiness, timekeeping, and quality of work

• Guaranteed - Jobs booked through Checkatrade are covered up to £1,000 (T&Cs apply)

Request a quote, search in the Checkatrade app, or enter your postcode below to find experienced extension builders near you.

FAQs

How long does it take to build an extension?

A small to medium-sized extension, like those found in typical semi-detached houses, usually takes around 1–3 months to complete. A larger or more intricate extension, featuring multiple stories or unique design elements, can take around 3–6 months or more to finish. Unexpected challenges such as structural issues or additional repairs can extend the project duration.

Do I need a specialist builder for an extension?

Extension builders have experience with structural work, sequencing trades and managing building projects safely, so it's worthwhile hiring an experienced extension builder for the work.

Is an extension worth the investment?

Often, yes, a well-built extension can increase living space, improve comfort and add value to your property.

Will an extension disrupt daily life?

Some disruption is expected during construction, but a clear plan and regular communication from your builder can help you plan ahead and minimise inconvenience.

For building extensions, should I employ house extension architects?

Hiring an extension architect is a smart choice if you're planning to add an extension to your home. Architects specialise in designing and planning buildings, offering design expertise, space optimisation, compliance, cost efficiency, and project management.

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